根据我们在日常检修工作中的调查,发现如图工所示结构(即前后从板座均铆在附加牵引梁上)的C_(20)型敞车,在按原型检修出厂后,运用不到一个厂修期,有的甚至只运用了几个月,即因牵引梁下垂过限(大部分下垂均在50毫米以上)需要返厂修理,严重的影响了车辆的正常运行,提高了修车成本。因此,必须予以彻底解决。为了解决这 According to our investigation in daily maintenance work, it was found that the C_ (20) gondola car with the structure as shown in the figure (that is, both the front and the back plate riveted on the additional towing beam) found that after using the prototype overhaul, less than one Plant repair period, and some even used only for a few months, that is due to the traction beam over the limit (most of the drooping are more than 50 mm) need to return to repair, seriously affecting the normal operation of the vehicle, increased repair costs . Therefore, we must completely solve it. In order to solve this